1. Field of the Invention
This invention relates generally to data compression and more particularly to data compression by eliminating unnecessary data representative of noise in related video frames.
2. Description of the Related Art
For motion compression by MEPG, MPEG treats the video as a frame unit, and uses differences between the continuous frames to perform compression. That is, compression relies upon the fact that the similarities between successive frames do not need to be repeatedly stored; instead, only the differences between the frames generally need to be stored.
Motion picture data converted to A/D contains noise (this noise is not photo's random noise) that varies per frame unit. However, to the human eye these noises are present even where sequential frames in the motion picture appear to be the same. For example, even when a motion-less object is recorded in a controlled environment, the resulting frame data will have different pixel values in the RGB domain.
A P-Picture for a system like MPEG uses difference data to perform motion compression. Compression rate increases where there is a lot of difference data. Since the noise data is treated as difference data, the compression rate decreases as a result of noise, even if the noise is for a picture having motion-less objects as described above.